Double activation with conditioning for sole attaching



April 1951 M. MAESER ET AL 2,549,981

DOUBLE-ACTIVATION WITH CONDITIONING FOR SOLE ATTACHING Filed Sept. 27,1949 9 Sheets-Sheet l 26 1 40 i zz [nven tors M'eth Maesez" Rabh E HobbSJn B r z'rA may .\w

April 24, 1951 M. MAESER ETAL 2,549,981

DOUBLE-ACTIVATION WITH CONDITIONINGFOR SOLE ATTACHING Filed Sept. 27,1949 -9 Sheets-Sheet 2 4 fiwen tom 47 Mz'et/z Maeser PaZp/z E. Hobbs Jr:

April 24, 1951 M. MAESER ET AL DOUBLE-ACTIVATION WITH CONDITIONING FORSOLE ATTACHING 9 Sheets-Sheet 3 Filed Sept. 27, 1949 lnven tors .Mz'ethMaeser' Ranh EHabbs' J n m r 0 u A .P w m U B April 24, 1951 M. MAESERET AL 2,549,981

DOUBLE-ACTIVATION WITH CONDITIONING FOR SOLE ATTACHING Filed Sept. 27,1949 9 Sheets-Sheet 4 Mz'ezh Maeser' Rqlph E H0663 Jr. 5' zhz'r 1 e I 9H April 24, 1951- M. MAESER ET AL $549,981

DOUBLE-ACTIVATION WITH CONDITIONING FOR SOLE ATTACHING Filed Sept. 27,1949 9 Sheets-Sheet 5 2,549,981 DOUBLE-ACTIVATION WITH CONDITIONING FORSOLE ATTACHING Filed Sept. 27, 1949 April 24, 1951 M. MAESER ETAL 9Sheets-Sheet 6 l v in! llll April 24, 1951 M. MAESER ET AL 2,549,931

ACTIVATION WITH CONDITIONING FOR SOLE ATTACHING DOUBLE- Filed Sept. 27,1949 9 Shee cs-Sheet 7 0 w M M m 0% %/I@ W .N m Wm HEP-Em m -EJIB w 3 MMW m I -i w ,6 I W 1 K m m I Mz'et/L .Mmsuser Ralph E Hobbs r:

M. MAESER ETALj 2,549,981 DOUBLE-ACTIVATION WITH CONDITIONING FOR SOLEATTACHING April 24, 1951 '9 Sheets-Sheet 8 Filed Sept. 27, 1949 Yr i lnven tors Mezh Maeser' Raoh E3 Hobbs Jr: By Zia! April 24, 1951 I M.MAESER ET AL 2,549,981

DOUBLE-ACTIVATION WITH CONDITIONING FOR SOLE ATTACHING Filed Sept. 27,1949 9 Sheets-Sheet) 9 I Thermosla! fl r link Inventors 94 Mz'ezh MaeserPatented Apr. 24, 1951 UNITED STATES PATENT OFFICE DOUBLE ACTIVATIONWITH CONDITIONING FOR SOLE ATTACI-IING Application September 27, 1949,Serial No. 117,966

This invention relates to apparatus for conditioning and treating shoematerials which are to be vadhesively attached. More particularly, theinvention is concerned with the provision of means for preparing solesfor attachment to shoe bottoms by rubber-like cement. While especiallyuseful in facilitating such attachment when the shoe materials are ofleather and the adhesive is readily heat-activatable only at rather hightemperatures, it will be understood that utility of the presentinvention is not so restricted, nor is it necessarily limited to soleattaching.

As pointed out in United States Letters Patent No. 2,367,629 granted toJan Teppema, certain adhesive compositions such as those comprisingbutadiene-acrylonitrile copolymer with a toughener therefor may beadvantageously employed to secure shoe parts together and maintain themin very tight relation. In contrast with neoprene base and othersynthetic rubber-type cements, not only are these compositions found tobe peculiarly effective in adhesively attaching a variety of materialscoated therewith, but, unfortunately, they also are found to have thecharacteristic of being activatable only at temperatures considerablyabove those at which the neoprene base types and some other adhesivesare heat activatable. It has been learned that an especially beneficialproperty of the butadiene-acrylonitrile type cement in shoemaking is itsability to retain L its capacity for being heat activatable afterprolonged drying times such as a month or more. But, for activation ofthis type cement within a short period of time convenient to shoemakers(about 15 seconds for soles) and corresponding With the production rateof certain shoe machinery, experience reveals that the requisite hightemperatures (about 400-450 F.) are ordinarily damaging and evendestructive to many leathers and other shoe materials unless appropriateprotective measures be taken. There is, moreover, a tendency for thecement activatable only at high temperature to set more rapidly whenremoved from the activating heat, and, lastly, the finding of asatisfactory solution to the activation problem is made more difficultby the fact that such high temperatures frequently tend to induceshrinkage and distortion of the heated surfaces.

For quicker and better attaching results, each of the two surfaces to bejoined should be roughened and bear a cement film. Also, the soleleather or other material should not have entirely lost its moisturecontent; that is, it should be in a pliable condition enabling it toconform 10 Claims.

and adhere closely to the curved shoe bottom or other contour. Excessivemoisture content in a sole, while imparting pliability, will, however,result in spotty and unacceptable edge and bottom characteristics uponapplication of activating heat. For cement attaching different materialspermanently, therefore, it Will be appreciated that a preparatoryoperation with an appropriate apparatus having control of temperaturesand moisture is highly desirable.

Having due regard for the above considerations and realizin that, forany adhesive surface, an evenly distributed activation is important, thepresent invention embodies two-Way activation. This is to say that theinfluence of the same source of activating heat is simultaneously di-'rected toward the sole cement and shoe bottom cement, for example. Bymeans of this principle, lower activating temperatures, better bondstrength over longer cementage, that is age of .cement afterapplication, and reduced danger of hydrolyzing the work are resultsobtained at lower operating cost.

In view of the foregoing, an object of the present invention is toprovide an improved means for more rapidly and satisfactorily preparingfor attachment work pieces having adhesive thereon that is readilyactivatable only at temperatures which are detrimental to them.

In accordance with this object, and inone aspect of the invention, afeature resides in preparing a sole for cement attachment to a shoebottom by directing a current of warm moist conditioning air against oneface (the grain side, for example) of the sole both before and thenwhile the influence of hot activating fluid is simultaneously directedupon its cement coated attaching face and the coated shoe bottom.

Another feature of the invention relates to the provision of convenientand novel apparatus for practicing the method just mentioned comprisingmeans for supporting a sole in a current of warm moist air, means foremitting hot dry air against the cement coated portions of said sole andits shoe bottom while supporting the latter, and mechanism forrelatively moving one of said means with respect to the other so thatsaid coated portions may jointly partake of the activatin heat whilesaid sole is being suitably tempered in moist air.

In an alternate aspect, a still further feature of the invention is theprovision of novel activating means which may be advantageouslyemployed, if desired, in lieu of the just mentioned hot dryair medium,said means comprising a conformable heating unit containingtemperature-controlled activating fluid and adapted to contact all, orsubstantially all, of the confronting cemented surfaces simultaneously.

With the above object and features in view, the invention will now bemore particularly described with reference to the accompanying drawings,in which Fig. 1 is a perspective view of an illustrative apparatusembodying the present invention;

Fig. 2 is a view partly in section and on a larger scale of an upperportion of the apparatus as viewed from the front of the machine (orfrom the left in Fig. 1) when subjecting a shoe and its outsole todouble activation, preparatory to sole attachment;

Fig. 3 is a side elevation, partly in section, of the air heating anddistributing mechanism shown in Fig. 1, the shoe sole support beingshown in its lowest position;

Fig. 4 is a plan view of a portion of the apparatus seen in Figs. 1 and3;

Fig. 5 is a perspective of a shoe and its outsole on their respectivesupports at an initial stage of treatment;

Fig. 6 is a perspective of the shoe and sole seen in Fig. 5 at asubsequent stage of their treatment;

Fig. '7 is a vertical section taken across the toe portion of the shoeand sole viewed in Fig. 6, and illustrating double activation duringsole conditioning;

Fig. 8 is a perspective of an alternate heat activating unit which maybe substituted in the apparatus for the dry hot air mechanism;

Fig. 9 is a plan view of the alternate form of heat activator seen inFig. 8;

Fig. 10 is a front elevation of the alternate activator when operatingon both sole and shoe;

Fig. 11 is a sectional view corresponding to Fig. '7, but illustratingthe conformability of the alternate activator to the contours ofcemented surfaces to be attached;

Fig. 12 is a rear elevation of the pump and motor mounting; and

Fig. 13 is a wiring diagram of the electrical sysstem for control of theapparatus.

For simplicity the illustrated apparatus is in the form of a singlestation machine. It will be understood that multiple station machinesfor treating rights and lefts would be of substantially similarconstruction except that the respective shoe and sole supports would bevented in a pattern corresponding generally to the right and leftcemented margins to be activated. As will become apparent, however,unless it is desired to prepare more than one shoe at a time for soleattaching, duplex construction is unnecessary when the alternate form ofheat activator is employed, as hereinafter disclosed.

Referring to Fig. 1, the apparatus is preferably supported by arectangular boxlike frame If) in which is fixedly mounted shelves [2, I4and I6 for purposes later to be explained. Detachably supported in anaperture formed in the top of the frame ID by brackets l8 afiixedthereto is a hollow metallic support for a shoe. This stationary support20 is of a shape such that its upper surface 22 has a longitudinalcontour complemental to the cemented shoe bottom to be activated. Foroperating on shoes differing considerably in bottom contour, other andmore suitably formed supports 20, not shown, may be secured to thebrackets 18, or the accommodation of shoe bottoms by a single supportmay be improved and broadened, as for example, by employing a shoesupport comprising two or more hollow sections consecutively hingedtogether.

The support 20 has a lower surface 24 (Fig. 2) preferably approximatelyparallel with the surface 22 for reasons which will become apparent. Thesurfaces 22 and 24 are provided with perforations or hot air emissionports 26 (Figs. 5, 6, '7 and 8) which are so spaced as to generallydefine and confront the usual cemented margins of the shoe bottom andattaching face of the sole which are to be activated for attachment.Spacing elements 28 secured to both surfaces 22 and 24 serve to separatethe cement film therefrom, thus assuring even dispersion of air blownthrough the ports 26.

Means are provided for directing into the shoe support 20 a steadycurrent of highly heated dry air. While any suitable mechanism foraccomplishing this may be employed, the preferred arrangement (Figs. 1,3 and 4) utilizes a blower 30 (Fig. 3) driven by an electric motor 31(Fig. 13). The blower is secured to one end of a hollow insulatedcylinder 32 which is aflixed to a rearward portion of the frame I0. Airtaken into the blower 38 at its inlet 34 is forced past an electricheater element 36 in the cylinder 32 to have its temperature raised. Atwo-way duct 40 connected to the other end of the cylinder 32 introduces the dry heated air into both the toe and shank portions of thesupport 20.

In juxtaposition beneath said shoe support 20 is a sole support 42mounted as will now be described (Fig. 2). Supported from the top of theframe It) and disposed diagonally of said supports is a pair of verticalguide rods 44, the latter being respectively secured to bosses 45integral with the frame by bolts 46 (Figs. 2 and 3). The shelf I6 issupported by bolts 41 received by the lower ends of the rods 44. Amoisture generating tank 48 rests on the shelf [6 and has a drain plug50 accessible through the latter. The sole support 42 includes in itsupper portion a screen 52 substantially parallel with surfaces 22 and 24of the support 20, and the screen is overlaid with foraminous materialsuch as a felt pad 54. Depending sides of the sole support 42 arearranged for telescopic movement relatively to the tank 48. The top ofthe latter is provided with a strip of rubber 56 extending for edgewiseengagement with said sides to prevent the escape of vapor at thisjunction. The lower limit of movement of the sole support 42 is fixed bystops 58 (Fig. 3) secured to the rods 44, a bracket 6|! afiixed to thesupport 42 having sleeves 62 slidable on the rods 44 between said stopsand the bosses 45.

For raising or lowering the sole support 42, one link 64 (Fig. 1) of atoggle is pivotally connected to the bracket 60. The other link 66 ofthe toggle constitutes an arm of a bell crank 68 pivotally connected toa crossbar of the frame [0. A treadle 10 pivotally mounted near the baseof the frame It! is connected to the bell crank 68 by a vertical link12.

Water from a water main is supplied to the tank 48 by an inlet pipe 14and via a valve 16 (Fig. 2). The latter is automatically regulated bymeans of a conventional float 18 so as to maintain a suitable waterlevel in the tank. The water is heated by means of a heating unitextending across the lower part of the tank, the unit being connected bywires in a conduit 82 to an electric control box 84. A thumb head 88mounted on the box 84 controls a thermostat 86 for regulating theheating unit 80 and the temperature of the water.

' For supplying warm moist air to the sole support 42, air is admittednear the bottom of the tank 48 by being forced under pressure through aperforated pipe 90. This air pressure is derived from acompressor 92driven by a motor 94, both compressor and motor being mounted on shelf Has best seen in Fig. 1 2. Before being conducted into the pipe 98 via ahose 96, the compressed air is preferably led through a filter 98mounted on the shelf Id to eliminate oil particles or other extraneousmatter. Tubing Hi0, connected to a valve 38 for a purpose subsequentlydescribed, is coiled about a portion of the heater 36 and is arranged toconduct compressed air directly from the pump 92 to the low portion ofthe felt pad 54 where the warmed air may be blown crosswise thereof.

A main switchl02 (Figs. 1 and 13) is' provided at the front of theapparatus and, when closed, a single auxiliary switch I04 may be thrownto energize the heater and blower relays and the air compressor motor94'. A variable transformer I06 mounted on the shelf I2 is provided witha dial and adjusting knob I 08 (Fig. 12) by which to set the desiredtemperature of air to be delivered by the blower so. 7

In an alternate form of the apparatus a dif ferently constructed shoeactivator support or receptacle generally designated I I0 (Figs. 8 to11,

inclusive) is substituted for the hollow support 20. Referring to Fig.8, the activator support I I0, secured as by brackets H2 to the top ofthe frame I0 and in juxtaposition to the sole support 42, comprises agenerally rectangular frame H4 having a longitudinal curvaturecorresponding to that of a shoe bottom. The top and bottom of the frameH4 are respectively covered by pliant sheets I It firmly anchoredagainst leakage as by strips H8, H9 and screws I (Fig. 11). The materialof the sheets H6 may be selected from any nonleaking fabric having thecharacteristics of being a good heat conductor, able to withstand hightemperature without breakdown, and not inclined. to pick up activatedcements. A sheet material found to be unusually satisfactory for thispurpose is afabric of spun glass impregnated with synthetic rubber. Areceptacle I22 serves as an inlet and overflow reservoir for liquidfilling the support H0. The liquid to be used is preferably an oilhaving a flash point of 500 F. or over. A heater I24 (Fig. 11) isimmersed in the oil and arranged in a loop having itsterminalsrespectively connected to wires leadingto the variable transformer I05.It will be apparent that the heater unit I24 supplants the air heatingmechanism otherwise associated with the shoe support 20.

In preparing an outsole O for attachment to the bottom of a shoe S bymeans of the apparatus of this invention, adhesive will first have beenapplied as a film A to a marginal portion of both the shoe bottom S andthe attaching face of the sole 0. It may be assumed for present purposesthat a rubberlike cement activatable only at rather high temperatures isbeing employed for better bonds and then, as is customary, the coatedworl: pieces have then been allowed to age for as much as a day orlonger. The operator of this apparatus may also operate a sole attachingmachine or serve as an assistant to the sole attacher. He will closeswitches I02 and I04 and. then adjust the water thermostat control 88 toprovide a vapor temperature of about 170 F. and the variable transformerknob I08 to provide an air flow temperature to the shoe support 20 ofCal With the shoe support 20 spaced from the sole support 48, as seen inFig. 5, the operator places the shoe bottom S on the surface 22, and thesole 0 is placed grain side down on the felt pad 54.. Then, either bystepping on the treadle I0 or by depressing the bell crank. 68 by hand,the op erator raises the sole support 42 to bring the flesh side of sole0 in close proximity to the surface 24 and under the activatinginfluence of the hot, dry air. No special efiort is made at this stageof operations to clamp the sole under any high molding pressure. Thus,while the shoe bottom is being activated by air escaping from the upperperforations 26,. the sole adhesive is also being activated by hot, dryair from the lower perforations 26, and the grain side of the sole 0 isbeing conditioned by the warm moist air directed thereagainst throughthe felt pad 54. Being thus rendered somewhat inert and pliable by thecirculating moisture the sole will more or less assume the contour ofthe sole support 42. It is important to note that the warm moist airserves bothto prevent burning or bydrolyzing of the work: pieces and toassure that they will: still be in moldable and activated condition somemoments later when removed to a sole attaching machine.

wetness or excess moisture causing spotty or otherwise unacceptablecondition on the sole tread surface is normally eliminated by the pad54. When steeply curved shoe bottoms are being worked. upon. or theapparatus has been steadily employed on many shoes an excess wetness mayaccumulate along the low portion of the pad 54.. To guard'against thisthe valve 38 may be opened so that the tube I063 delivers a stream ofair heated somewhat by the heater 36 and so vapor-ices the excessmoisture in this region.

In about fifteen seconds for ordinary leather, or for longer periods atlower temperatures, if more convenient, the operator may release thetreadle 10 or cell crank. 68 to separate the sole support 42 from theshoe support 20. The activated cement surfaces are ready for adhesionand the work pieces may be removed from the machine, spotted on oneanother, and delivered to the sole attaching machine for the applicationof suitable pressure. Transfer to this machine need not be madehurriedly, however, as the activating effect will be prolonged by thevapor treatment, and the sole is in no danger of grain cracking when theattaching pressure is applied.

The manner of using the alternate heat activator H0 in lieu of thesupport 20 is essentially as just described for operating the latter.The activator H0 is frequently found especially convenient in that anoperator will not be subjected to uncomfortable operating temperaturesalthough the oil is kept at 400450 F., and the operating cost may besomewhat lower without slowing down the attaching process. Also, sincethe activator H0 is conformable and will be in intimate contact with thecontours of any coated surface to be attached, items other than solesand shoes may be placed thereagainst for double activation duringconditioning.

Having thus described our invention what we claim as new and desire tosecure by Letters Patent of the United States is:

1. Apparatus for conditioning a sole and simultaneously activatingadhesive on said sole and a shoe bottom, said apparatus including a solesupport arranged for contact with warm moist air, and a heating unit injuxtaposition with said sole support having one side shaped to conformwith a sole thereon and another side shaped to conform with a shoebottom.

2. Apparatus for preparing a cemented sole and shoe bottom for adhesiveattachment to one another comprising a perforate support for said solehaving the general contour of said shoe bottom, a heat activating unitin juxtaposition with said sole support and having opposite surfacesconformable with said general contour, means for directing warmconditioning vapor about said support, and means for directing heatedfluid into said unit. 7 3. Apparatus for preparing one cemented shoepart for adhesive attachment to a second comprising a conditioningchamber, a vapor generator operatively connected therewith, a supportfor said first part movable in the chamber and having a surface shapedto conform with the attaching face of the second part, and a two-wayheat activating unit disposed for intimate engagement with the attachingface of said first part on said support, said unit also serving as aconformable support for said second part.

4. Apparatus for conditioning a sole and simultaneously activatingadhesive on said sole and a shoe bottom, comprising a conditioningchamber, means for generating warm vapor in said chamber, a perforatesole support for exposing the sole to the vapor in the chamber, aheating unit adjacent said chamber having opposite surfaces respectivelyadaptable to conform with said sole and shoe bottom, and means forrelatively moving the sole support and heating unit together and apartwhereby sole tempering may be effected during two-way activation by saidunit.

5. Apparatus as set forth in claim 4 further characterized in thatcontrols are provided for independently governing both the conditioningtemperature within said chamber and the activating temperature of saidheating unit.

6. Unitary apparatus for activating a cemented sole and shoe bottomwhile conditioning said sole, comprising a sole support including asurface complemental to said shoe bottom, means for moving said supportwith a sole thereon while the latter is in contact with warm moist air,and a heating unit mounted in the path of said sup- 8 port havingactivating faces also complemental to said shoe bottom, one of saidfaces being arranged to cooperate with said surface during contact withsaid sole.

7. A heating unit for activating the cement coated portions of two workpieces to be adhesively attached comprising a receptacle for oil, frameportions of the receptacle generally defining the contour of theattaching faces, means for controlling the temperature of the oil, andpliant heat-conducting coverings for the opposite sides of saidreceptacle, said coverings being in contact with the oil andrespectively conformable to an attaching face.

8. A heating unit as set forth in claim 7 further characterized in thatsaid coverings respectively comprise a fabric of spun glass impregnatedwith synthetic rubber.

9. Apparatus for preparing a leather part of a shoe for adhesiveattachment, comprising a formed support engageable with a non-attachingface of the part to be treated, means for subjecting the part to warmmoist air, a conformable heat activating unit in juxtaposition to thesupport, and means for relatively moving the unit and the supportwhereby the attaching face of the part is located in proximity to theunit and thereby activated during conditioning of the remainder thereof.

10. Apparatus for preparing a cemented sole and a cemented shoe bottomfor adhesive attachment, comprising a formed sole support, a twoway heatactivating unit arranged and adapted to treat the shoe bottom, means fordirecting warm moist air about the sole on said support but not to theshoe bottom, and means for relatively moving said support and unitwhereby the activating effect of the latter is also influential in thevicinity of said support.

MIETH MAESER. RALPH E. HOBBS, JR.

REFERENCES CITED UNITED STATES PATENTS Name Date Borge Mar. 14, 1933Number

